Services research has shown that depressive disorders are common, with a prevalence of 15-20%, in primary care. The diagnostic categories currently in use to classify these patients, and ultimately to guide their treatment, have come from the speciality sector of psychiatry. Recent epidemiologic research has shown that these speciality derived categories have limited applicability in primary care, and that there are other depressive disorder presentations in primary care which do not easily fit into the available categories of the official psychiatry nosology. The specific aim of this proposal is to obtain longitudinal outcome data on four depressive disorder presentations established as common in primary care. The four disorders include two which have been previously defined (RDC episodic minor depressive disorder; RDC chronic intermittent depressive disorder) and two which are suggested by DSM-II categories but which are not well defined under that system (mixed anxiety depression and suspected/masked depression). Explicit criteria for the latter two categories will be developed and tested for reliability and comprehensibility to primary care providers. The study then follows a longitudinal design, obtaining clinical outcome data by psychiatric interview one year after each targeted depressive disorder has been identified by the primary care provider. The outcome data will include treatment response to a commonly recommended anti-depressant, imipramine, as well as course and functional status over the one year follow-up interval. The focus of this research is on depressive presentation as they occur in the routine day-to-day practice of primary care providers. It seeks to establish valid categories for those presentations which will be accepted by primary care providers and which will relate directly to management and treatment.